When objects are not moving or moving at a constant speed, the forces on them are balanced. We are going to try and balance the force of gravity and the force from a hair dryer’s air stream on a table tennis ball.
You will need
- 1 Table tennis ball
- 1 Hair dryer
What to do
- Point the hair dryer upwards and turn it on.
- Carefully place the table tennis ball in the air stream.
- The table tennis ball should float in the hair dryer’s air stream.
- You might have to play with the strength of the air flow to get things exactly right.
- If you get it to work, try to tilt the hair dryer and see how far you can tilt it, before the ball falls off.
- When the table tennis ball is floating the forces of the hair drier’s air stream and gravity are exactly balanced.
You can also watch this experiment on YouTube: